Let's not kid ourselves, this 'third place' is just a euphemism for 'IRC in 2010'. We'll have partial moderation because people don't have the opportunity to act like asses (it's tied to their host site account, which can be yanked if anything happens) but you may need active moderation. I propose the following:

Have a moderator side switch that can 'box' someone from chat. (We'd never see this)

Allow 10k'rs to vote to 'muzzle' a user (put them in timeout for x number of minutes)

Have a flagging system.

The problem with an active moderator is that they have to be there all the time; I recommend making the system as automated (or crowd-sourced) as possible, so that we'll never have a need for a human 'moderator'.

Those are all very good questions, and not all of them have answers yet. A big part of the currently running preview beta is seeing the chat in action. Not just from a technical standpoint, but also from a social one.

We need to see actual user behavior, so we know what problems can occur and how they might have to be handled. Let's hope we know more at the end of the three days :)

Interesting, as far as crowd sourcing, how about a system that prompts people with sufficiently high rep asking if they would like to moderate for this session.

I would like something a little more complex than "more than 10k rep" especially given that there are 20 pages of 10kers on SO. How about something like >10k rep + in the top 10% of users to keep the number of cooks in the kitchen down.

Also there should obviously be some sort of moderator limit per room, something like 2 or 3 moderators max, then nobody else gets asked until someone leaves. cycle through people still in the room that meet the first requirement, highest to lowest rep?